In recent years, technologies for displaying images (captured images) captured by in-vehicle cameras on monitors mounted in vehicles have been developed as rear field-of-view support systems configured for drivers to check behind the vehicles. The drivers can confirm a state of the surroundings of their vehicles by viewing the monitors instead of mirrors such as rearview mirrors or sideview mirrors.
On the other hand, systems configured to detect objects (for example, other vehicles or the like approaching from the rear sides) coming relatively close to one's vehicle using the captured images or various sensor devices or the like mounted on the vehicle and notify a driver that such objects (approaching objects) are approaching have been developed. For example, PTL 1 discloses a technology for sensibly notifying a driver of a distance between a vehicle and a nearby obstacle by measuring a distance between the vehicle and the obstacle using a distance measuring sensor and causing a plurality of LEDs to emit light stepwise according to the measured distance.
Here, as a technology for calling the attention of a user by appending a predetermined pattern to a specific object in an image, for example, PTL 2 discloses a technology for notifying a user of a spot which can become defective at the time of combination of images by attaching a zebra pattern to the closest subject in a captured image when a distance up to the closest subject is less than a predetermined threshold value, in a system that combines images captured by a plurality of imaging units and generates a panorama image.